Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 57, NWS Lake Charles, LA

September 15, 2021Avoyelles Parish, Evangeline Parish, Saint Landry Parish, Louisiana

NWS Lake Charles, LA issued this flash flood warning at Sep 15, 2021, 3:15 AM CDT for Avoyelles Parish, Evangeline Parish, Saint Landry Parish, Louisiana. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Sep 15, 2021, 3:15 AM CDT (08:15 UTC)
Expired: Sep 15, 2021, 6:00 AM CDT
In force: 3 hr
Issued by: NWS Lake Charles, LA
Area: Storm-based polygon
Flood severity: None

Counties Avoyelles Parish, LA, Evangeline Parish, LA, Saint Landry Parish, LA

The radar

The Ft Polk radar (KPOE), 105 km from the middle of the area, began a volume at 08:15 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 8.3 hours before the alert went out and 158 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 254 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 585 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 110 m²/s²
0-3 km storm-relative helicity: 218 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

796 
WGUS54 KLCH 150815
FFWLCH
LAC009-039-097-151100-
/O.NEW.KLCH.FF.W.0057.210915T0815Z-210915T1100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Lake Charles LA
315 AM CDT Wed Sep 15 2021

The National Weather Service in Lake Charles has issued a

* Flash Flood Warning for...
  Central Avoyelles Parish in central Louisiana...
  Northeastern Evangeline Parish in central Louisiana...
  Northeastern St. Landry Parish in central Louisiana...

* Until 600 AM CDT.

* At 315 AM CDT, Doppler radar indicated heavy rain across the 
  warned area. Between 2 and 4 inches of rain have fallen. 
  Additional rainfall amounts of 2 to 4 inches are possible in the 
  warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Simmesport, Melville, Moreauville, Palmetto, Bayou Current, 
  Morrow, Bordelonville, Cottonport, Plaucheville, Dupont, Goudeau, 
  Big Cane, Lebeau, Big Bend, Whiteville, Lake Ophelia National 
  Wildlife Refuge, Grand Prairie and Hamburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3083 9215 3100 9204 3123 9201 3123 9192
      3127 9195 3130 9191 3123 9179 3120 9169
      3117 9168 3113 9172 3110 9170 3104 9172
      3098 9181 3087 9180 3086 9182 3071 9173
      3063 9174 3062 9200 3065 9217 3065 9218

FLASH FLOOD...RADAR INDICATED

$$

Rua

The office that day

Everything else NWS Lake Charles, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 14, 7:21 PM CDT	Wind Advisory	LCH	Cameron	72 min
Sep 15, 1:45 AM CDT	Flash Flood Warning	LCH	Avoyelles, Evangeline, Rapides, Saint Landry	4 hr
Sep 15, 11:13 AM CDT	Areal Flood Warning	LCH	Avoyelles, Evangeline, Rapides, Saint Landry	6 hr

Nearby

Flash Flood Warnings in Louisiana, 2021 Every flash flood warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.